The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
The recent rise in oil prices leads vehicle manufacturers to a more competition to improve fuel efficiency. In the case of engines, efforts are being made to reduce weight and to improve fuel efficiency through technologies such as downsizing.
Meanwhile, among the fuel efficiency improvement methods that can be pursued in a transmission mounted in a vehicle, there is a method for improving fuel efficiency by enabling an engine to operate at a more efficient operating point by multi-staging the transmission.
In addition, multi-staging of such a vehicular transmission may further improve the quietness of the vehicle by enabling the engine to operate in a relatively low RPM zone.
As the number of transmission stages of a transmission increases, the number of internal components constituting the transmission increases, which may deteriorate the mountability, costs, weight, and transmission efficiency of the transmission. Therefore, in order to increase a fuel efficiency through the multi-staging of the transmission, it is important to devise a transmission structure that can increase efficiency with reduced components and a relatively simple structure.
It should be understood the foregoing description of the background art is merely intended to enhance the understanding of the background of the present disclosure and should not be construed as an admission that it is a prior art already known to a person ordinarily skilled in the art.